Fuel oil composition



Patented Oct. 10, 1950 FUEL OIL COMPOSITION Calmy Wies, New York, N. Y., and John B; R.

Caron, North Plainfield, and Everett B. Glendenning, Cranford, N. J., assignors to Shell Development Company, San Francisco, Calif., a

corporation of Delaware No Drawing. Application June 7, 1948, Serial No. 31,596

This invention pertains to improvement of hydrocarbon fuels and more particularly to fuel oil compositions capable of preventing or inhibiting the sludging and/or clogging tendencies generally exhibited by hydrocarbon fuels, such as those utilized in burner systems, tanks, Diesel and combustion engines, and various other industrial and domestic equipment. In addition, this invention relates to fuel oil compositions capable of removing preformed deleterious matter from filters, screens, and the like, caused by deterioration and/or the presence of foreign bodies, e. g. water in the fuel oils.

Hydrocarbons, such as distillate fuels, for example,- those having a normal distillation range of from about 300 F. to 700 F. and particularly those fuels having a distillation range of from about 340 F. to about 640 F., generally have a marked tendency to deteriorate under oxidizing conditions, and to form sludge. Also, thepresence of impurities in such fuels, such as the presence of moisture, dispersed water, organic and/or inorganic foreign matter, and the like, cause the formation of insoluble products which tend to settle out and adhere to surfaces with which they come in contact, thereby in turn, causing clogging or plugging of filters, strainers, screens, conduit lines, and the like, of the equipment in which they are used. This necessitates frequent cleaning and even replacement of parts, thereby markedly decreasing the performance efliciency of various equipment which utilizes such fuel oils.

The problem of screen clogging is common, particularly in domestic fuel oilsystems employing distillate fuel oils produced by distilling or cracking of petroleum which fuels are characterized by their relatively low viscosity and other properties. Fuel oils of this type generally conform to the specifications set forth in Commercial Standards 0. S. 12-40 for Nos. 1. 2, and 3, Fuel Oils. Petroleum distillates within the ranges specified and which generally do not exceed 700 F. and preferably are below 675 F. for use as Diesel fuels are further examples of the type of oils which under conditions described have a tendency towards screen or filter clogging. partation of sludge materials which, in, turn, deposit Ill 14 Claims. (CI. 44-62) on and clog the screens or filters used for protecting the burners or engines, which use such oils as the fuel.

It is an objec of this invention to inhibit sludging tendencies f hydrocarbon fuel oils. It is another object of this invention to inhibit sludging and .precipitation of contaminants in hydrocarbon distillate fuel oils and particularly in cracked hydrocarbon fuels. It is still another ob jectof this invention to provide distillate fuel oils and particularly fuel oils obtained during cracking of hydrocarbons, which have excellent performance characteristics with respect to freedom from screen clogging, even after extensive storage under oxidizing conditions and in the presence of water. Still another object of this invention is to provide a distillate fuel oil composition which is effective in removing preformed sludge deposits formed in fuel oil systems. Stillanother object of this invention is to provide a particular type of distillate fuel oil compositions, and blends thereof, which are non-corrosive and stab e, and which are efiective for cleaning and sludge removing.

The above and other objects of this invention may be attained by dispersing, admixing or dissolving in hydrocarbon distillate fuel oils, which normally have a tendency to cause clogging or plugging of screens, filters, conduit lines and the like, a minor amount, which amount, however,

is suflicient to inhibit said tendencies, of a polyhydric alcohol-polybasic acid resin and/or a modified resin of this type, and a detergent salt. If desired, a glycol-ether type drying agent may be admixed with the synthetic resin and detergent salt mixture or to thefuel composition containing these additives. g

The hydrocarbon distillate'fuel oils in which the active ingredient of this invent on are'dispersed or blended with may be treated or untreated catalytically'cracked fuel oils, ormixtures of cracked fuelswith straight run fuel oils having components normally/ distilling at about 500 F. and having an end distillation po nt not exceeding 700 F. Generally such fuels of the type under discussion have aboiling range of from about 340 F. to about 700 F. and preferably have a boiling rangeof from about 400 F. to

. about 675 F.

Cracked fuels may be obtained by thermal 'or catalytic cracking of certain petroleum hydrocarbon feed stocks. Both the cracked fuels as well as blends of cracked and straight run fuels may be acid or caustic treated to improve their stability. Specifically hydrocarbon distillates which are utilized as bases in compositions of this invention are cracked gas oils, fuel oils, furnace oils, burner oils, Diesel fuel oils, kerosene,

etc., and mixtures of said cracked fuels with Fuel 13-44% acid treated clay iii- Fuel A- tered sltraiggltg lgl ata ytica y gas 0 an 0 Proper cracked caustic washed,

gas oil clay filtered catalytically cracked gas oil Gravity. API 31.0 32.4 Color. NPA ll+ Ila-i- ASTM 434 410 EBP. 620 670 Sulfur, Per Cent Weight. 0.783 0. 79 Pour point, I? 5 The primary additives of this invention which possess the unique property of inhibiting sludge formation or removing preformed deposits from surfaces, thereby preventing clogging of systems utilizing fuels normally susceptible to such deterioration are synthetic resins, particularly the polyhydric alcohol-polybasic acid resins, generally known as alkyl resins.

The acids or their anhydrides which may be used to form the resins are phthalic, succinic, maleic, malic, malo-malic', diphenic, citric, tartaric, camphoric, benzophenone dicarboxylic acids and mixtures thereof.

The polyhydric alcohols suitable for forming the resin with acids of the above type are glycol and homologues, glycerol and homologues, sorbitol, mannitol, erythritol, pentaerythritol, polyglycols,etc.'

Various methods may be used for forming the resinous material. The simplest method being to heat the polyhydric alcohol and the polybasic acid, with or without modifying ingredients until resinification is substantially complete. The resinous material should possess some degree of solubility in a liquid hydrocarbon fuel or be readily dispersible therein. By modifying agents is meant to include such materials as drying oils,

semi-drying oils and/or non-drying oils and derivatives or fractions thereof free fatty acids, naphthenic acids, etc, which can be admixed with and reacted with the polyhydric alcohol and polybasic acid to form the resinous product.

The mol ratio of the reacting ingredients may vary over wide limits and generally about 1 to 3 mols of the polybasic acid may be used for each mol of polyhydric alcoholused.

Typical compositions of the polyhydric alcoholp'olybaslc acid resins are as follows:

Resin A made from glycerol and phthalic anhydride Resin B made from glycerol and maleic anhydride Resin C made from ethylene glycol and phthalic anhydride Resin D made from diethylene glycol and phthalic anhydride Resin E made from mannitol and phthalic anhydride Resin F made from erythritol and phthalic anhydride Resin G made from glycerol and malic anhydride Resin H made from glycerol, phthalic anhydride and castor oil Resin I made from glycerol, phthalic anhydride and linseed oil Resin J made from glycerol, phthalic anhydride and linseed oil acids The amount of a polyhydric alcohol-polybasic acid resin which can be used to form a' base composition of this invention, may vary from about 5% to about 35% and preferably from about 10 to about 30%.

If desired and under certain conditions of use, it is preferred to add detergents to compositions of this invention. The function of the detergent agents in compositions of this invention appear to act as peptizer and thereby prevent the settling and adhering of impurities and sludge and allowing them to pass through the screen or filter system.

Detergents which may be used are alkali, alkaline earth and heavy metals and organic nitrogen base salts of various organic acids. The acidic portion of such detergents may be naphthenic acid, sulfonic acids, aromatic and hydroxy aromatic carboxylic acids, aliphatic acids, said acids containing, if desired, substituent groups, e. g. an amino, hydroxide, mercapto, halogen and sulfur groups and the like. Also phenates, alcoholates, carbamates, thiocarbamates, xanthates, etc., may be used.

. Particularly preferred class of detergents are the salts of alkyl substituted phenol sulfides or its selenide and/or its telluride equivalent. These phenolic salts may be represented by the general formulas wherein M is a metal; R and R represent at least one alkyl radical attached to the aromatic ring Ar, the total number of carbon atoms in all of such radicals being at least 5; X is O and/or S; Q is S, Se or Te and n is an integer of from 1 to 4.

To form the salts of these phenolic compounds they may be treated with such metal compounds as Li, Na, K, Cu, Hg, Fe, Mn, Mg, Ca, Ba, Sr, Pb, Ni, Co, Cr, Sn, Fe, etc. Alkaline earth metals are particularly preferred because of their solubility in hydrocarbons and potent detergent properties.

In addition to the normal salts of phenolic compounds, basic salts may be used and can be represented by the formula M-XH L I-XII wherein the symbols are the same as referred to in the previous formulas. These basic salts may be formed by reacting the aromatic acidic compounds with more than the amount of metal sp'from naph- Continent '1 salt of theljspecificktype of.- petroleum sulfon ac'idjunde'r discussion may be added T to ,the ;concliti i ie' or, base from about 5 r lls and preferablyjlbelow10%. 'j 1 In systemsfwherein substantial?amounts of moisture are present afdryinga'gent may be added which is compatible"withf,the active inj n q f h i f i venti n, B y 1 most 40 ofjjthefree moisture 'in this manner, the amount whichwoulcl normally combine with sludge forming" materials is "diminished; thus alleviating a most] aggravating clogging problemj] Drying agents which; are particularly" suited are the sl c e t e iti'pesu' ha .i eth 'le s ycol monomethyl', thyl N :and isoprop'yl ether, diethylene fl glycol monof-butylf ether, diethylene glycol" monodecy V tlier, etc; j also 'Jdipropylene glycol mono eth yl ether, dipropylene glycol 5 mono-isopropyl ether; 'dipropylene glycol monoisioamyl ether; diisobutylene glycol-mono isopropyl ether, fethylenewropylene glycol. mono ethyl ether, ethylene-isobutylene "glycol-monoisoproylether, etc. Instea do fthe glycol-ethers, various alcohols may be used such as; diols having 6 or more 'carb'onfatoms in the molecule, such as hexyleneglycoLjt, ec ylene glycols f cetylene yco sJ c-i cq uth s ip cpyiene slyc018; fisiibu lsne l col; flim sn i. s' wq ether so alcohols a dpartico er'ly the "glycol monofalkyl ethers, leifgl,"thecellosolves such a'sj ethylene glycol "mono ethyl ether, ethylene glycol mono propyl ether; ethylene If glycol; mono tert-butyl ether, ethylenej'glycol mono hexyl ether, propylene glycol mono I ethyl ether; propylene glycol mono isoamyl ether, etc,,g. Also 'glycerine and the likemaybeusedf J l L N The amount" of these drying agentmaterials, when used, ,constitute'sa substantial portion of the base and generallyfis around about 50% or more. However, under certain'conditions these materials may be omitted from the base.

siesta forth be referred to-as Composition A may con-- slat of Composition vA General Limited Range Range Per Cent Per Cent Polyhydroxy alcohol-polybasic acid resins 6-85 10-30 Detergents, e. g. barium salt of an alkyl phenol sulfide and/or calcium petroleum suiionate or the like 5-15 10 or less Drying agent, a. g. diethylene gl butyl other. 025 0-20 Hydrocarbon distillate iueloil balance balance Specific base compositions may be illustrated by the following examples:

Composition B The following table further illustrates suitable anti-clogging base compositions Components 1 2 3 4 Surface active agent Glycerol-phthalic anhydride resin x x Glyoerol-maleic anhydridc resin Ethylene glycol-phthalic anhy e resin Manniiol-phthalic anbydride resin Detergent Ba salt of alkyl phenol sulfide x Ca salt of alkyl phenol sulfide. Na nanhthenate Na petroleum sulfonate Ga petroleum sulfonate Drying agent Diethylene glycol monobutyl ether.-. Diethylene glycol monoethyl ether. Cetylene glycol x All of the above compositions are diluted with a hydrocarbon distillate fuel oil in amounts indicated above.

Compositions of this invention are addedgenerally mixed in amount of 1 pint or less with from about 250 gallons to about 1000 gallons of fuel oil. Thus, for example, on a percentage basis/of fuel used, one pint of any one of the compositions described above per 250 gallons of fuel would correspond to approximately the following concentration of the active ingredients:

Per cent Polyhydric alcohol-polybasic acid resin 0.0025 to 0.005 Detergents, e. g. Ba salt of alkyl 7 phenol disulfide 0.0025 to 0.0042 Drying agent (glycol-ether)--- 0 to 0.002

Compositions B and D when added in amounts of approximately 1 pint per 250 gallons of fuel oil correspond approximately the following concentrations of the active ingredients present in the final composition.

Composition 3' Per cent To inhibit corrosive tendencies of the non-polar organic liquids a minute amount of caustic or aromatic nitrogen compound such as aniline may be added. These compounds act as alkaline reserves and render the fuel substantially non-corrosive to copper, brass and other metals. go

The following examples illustrate the effectiveness of compositions of this invention: ,4

Example I f A fuel tank was cleaned with acetone and the entire system flushed with kerosene and the tank charged with 250 gallons of fuel oil (B) as noted in column 3. The oil was steamed with saturated steam for about 1% minutes. In other tank 1 pint of composition B was added to 250 gallons of the above fuel oil and steamed in the same manner.

Both oils were circulated through a pump and strainer system for 28 days and the appearance of the system and oil noted.

Unrioped Fuel 13 and Undoped Fuel Oil B Composition B (i it/250 gallons) Strainer basket 100% covered with is Several small spots of inch thick layer of fiber and lint; no black emulsion. stain. Screen dlSkS---- Completely covered Narrow ring of sludge with black emulsion at outer edge adiaabout He" thick. cent to cork gasket. Tank Medium to heavy eoat- Very slight amount of mg of light grey sludge sludge. on bottom and sides.

To compositions of this invention may be added minor amounts of a foaming inhibitor such as 550 silicon liquids, e. g. dimethyl silicone; fluoro organic compounds, fluoro paraiiins, salts of alkyl alkylene phosphates and the like. Compositions of this invention may be used to remove deposits, formed on metal surfaces such as in tubes, evaporators, heat exchangers, distillation and cracking equipment and the like. They are non-corrosive and do not interfere with the functioning of the fluid in which dispersed.

It is to be understood that while the features 0 of the invention have been described and illustrated in connection with certain specific examples, this invention, however, is not to be limited thereto or otherwise restricted, except by the prior art and the scope of the appended claims.

We claim as our invention:

1. A non-clogging fuel oil normally susceptible to cause clogging containing in combination therewithabout 0.005% glycerol-phthalic anhydride resin and about 0.0025% barium salt of alkyl phenol disulfide. g

2. A non-clogging fuel oil normally susceptible to cause clogging containing in combination therewith about 0.005% glycerol-phthalic anhydride resin, about 0.0025% barium salt of alkyl phenol disulflde and a minute amount of diethylene glycol monobutyl ether.

3. A non-clogging fuel oil normally susceptible to cause clogging containing in combination therewith about 0.005% glycerol-maleic anhydride resin, about 0.0025% barium salt of alkyl phenol disulflde.

4. A non-clogging fuel oil normally susceptible to cause clogging containing in combination therewith about 0.005% glycerol phthalic anhydride resin and about 0.0025% calcium petroleum sulfonate.

5. A non-clogging fuel oil containing a substantial amount of cracked hydrocarbon fractions normally susceptible to cause clogging containing in combination therewith about 0.005%

glycerol-phthalic anhydride resin and about 0.0025% barium salt of alkyl phenol disulfide.

6. A non-clogging fuel oil containing a substantialamount of cracked hydrocarbon frac tions normally susceptible to cause clogging containing in combination therewith about 0.005% glycerol-phthalic anhydride resin ,and about 0.0025% calcium petroleum sulfonate.

7. A non-clogging fuel oil containing a hydrocarbon fuel oil from the group consisting of cracked and mixtures of cracked and straight run fuel oil normally susceptible to cause clogging containing in combination therewith about 0 0.005% glycerol-phthalic anhydride resin and about 0.0025% barium salt of alkyl phenol disulfides 8. A non-clogging fuel oil containing a hydrocarbon fuel oil from the group consisting of cracked and mixtures of cracked and straight run fuel oil normally susceptible to cause clogging containing in combination therewith about 0.005% glycerol-phthalic anhydride resin and about 0.0025% calcium petroleum sulfonate.

9. A non-clogging fuel oil normally susceptible to cause clogging containing in combination therewith from about 0.0025% to about 0.005% of a polyhydric alcohol-poiybasic acid resin, from about 0.0025% to 0.0042% of a salt of an organic acidic compound and from about 0 to about 0.002% of a glycol-ether.

10. A non-clogging fuel oil normally susceptible to cause clogging containing in combination therewith from about 0.0025% to about 0.005% of a polyhydric alcohol-polybasic acid resin, from about 0.0025% to 0.0042% of a salt of an organic acidic compound.

11. In a system having small orifices which are normally subject to clogging by liquid hydrocarbon fuel oils, the method of inhibiting such clogging by employing in said systems a liquid hydrocarbon fuel oil containing about 0.005% glycerol-phthalic anhydride resin and about 0.0025% barium salt of alkyl phenol disulfide.

12. In a. system having small orifices which are normally subject to clogging by liquid hydrocarbon fuel oils, the method of inhibiting such clogging by employing in said systems a liquid hydrocarbon fuel oil containing about 0.005% glycerolphthalic anhydride resin and about 0.0025% calcium petroleum sulfonate.

13. In a system having small orifices which are normally subject to clogging by liquid hydrocarbon fuel oils, the method of inhibiting such clogging by employing in said systems a liquid hydrocarbon fuel oil containing about 0.005 glycerol-maleic anhydride and about 0.0025% baribon fuel oils; the method of inhibiting such clogging by employing in said systems a liquid hydrocarbon fuel oil containing a minute amount of a polyhydrlc alcohol-polybaslc acid resin and a salt of an organic acidic compound.

CALMY WIES. JOHN B. R. CAR/ON.

EVERETT B. GLENDENNING.

' 1c REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,230,642 Fischer et a1. Feb. 4, 1941 2,301,795 Proell Nov. 10, 1942 2,369,490 1 Proell Feb. 13, 1945 

1. A NON-CLOGGING FUEL OIL NORMALLY SUSCEPTIBLE TO CAUSE CLOGGING CONTAINING IN COMBINATION THEREWITH ABOUT 0.005% GLYCEROL-PHTHALIC ANHYDRIDE RESIN AND ABOUT 0.0025% BARIUM SALT OF ALKYL PHENOL DISULFIDE. 